Molding Process And Products Formed Thereby

ABSTRACT

A process for producing molded products having portions formed with two separate materials is provided. The process involves forming a first component over a structural core in a first step, and forming a second component that is secured to the first component and the core in a second step. The second component can be formed directly over the first component or can be secured thereto after formation. The first and second components can additionally be formed with indicia thereon, or with recesses within which inserts containing the desired indicia can be positioned. Additionally, the first component can be formed with a ridge disposed on a projection formed on the first component that effectively seals off a portion of the first component when the second component is formed around the core and the first component to ensure the portion of the first component surrounded by the ridge remains visible after formation of the second component.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims priority as a continuation of U.S.Non-Provisional patent application Ser. No. 12/538,439, filed on Aug.10, 2009, now U.S. Pat. No. 8,641,955, issued on Feb. 4, 2014, which inturn claims priority from U.S. Provisional Application Ser. No.61/087,365 filed on Aug. 8, 2008, the entirety of which are eachexpressly incorporated by reference herein.

FIELD OF THE INVENTION

The present invention relates to molded items, such as handles forvarious types of tools such as tools utilized in the medical industryincluding torque wrenches, and, more specifically, to an item having anexterior formed from a two step molding process to provide the desiredappearance and properties to the item.

BACKGROUND OF THE INVENTION

Many different types of items are formed from molded components. Thesecomponents are formed in molding processes that use a desired materialin fluid form that is introduced into a mold to be shaped and solidifiedinto the desired to form the item. However, in many of these processes,the item is limited to being formed from only a single type of material,due to various constraints, including the types of material beingutilized in the molding process.

In order to provide various items with improved aesthetic andutilitarian properties, many items have previously been formed from orwith multiple molded components. In these items, the components arenormally formed separately from one another and later mechanicallyinterlocked with one another, or otherwise secured to one another toform the item or a portion of the item. On many occasions, the manner inwhich the molded components are secured to one another often provides aless than desirable appearance and/or a less durable construction, aswell as increasing the overall expense for the manufacturing andassembly of the components.

In addition, in certain situations where the item having the multiplemolded components is to be subjected to conditions far outside of normalenvironmental conditions the need for a durable item is paramount, suchas in the medical field where molded items are often autoclaved tosterilize the items after use. This is because the conditions utilizedto sterilize the items including the molded components can easilydegrade or separate the components from one another, thereby damagingthe item. In addition, should the components become separated from oneanother in any manner, that separation can enable various bacteria andother similar organisms to enter the separation present between thecomponents and potentially prevent the item from being properlysterilized.

Therefore, it is desirable to develop a process for molding an item,such as a tool for use in the medical field, with multiple moldedcomponents that provides a tool with the required durability for themolded components in the item, but that also provides a clean andaesthetically pleasing appearance to the item.

SUMMARY OF THE INVENTION

According to one aspect of the present invention, the molding processinvolves providing a core for the item on which the various materialsare to be molded. The core is positioned within a mold having thedesired shape for the first molded component, and the material used toform that first component is subsequently injected, or otherwiseintroduced into the mold. The first component is formed with one or morestructural features thereon that enable a second molded component formedof the same or a different material to be directly secured to the firstcomponent, such as in a subsequent molding process where the moldutilized in the subsequent process defines a desired configuration forthe second component around the core and the first component.

According to another aspect of the present invention, because the secondmolded component can be affixed directly to the first molded componentin a variety of different manners, such as by molding the secondcomponent directly around and/or onto the first component, the materialsutilized to form the first and second components can be selected to beeasily adhered or affixed to one another and to provide the desiredaesthetic appearance to the item.

According to still another aspect of the present invention, the firstand second components can be formed of materials having differentcolors, textures, and/or other properties to enhance the appearance andfeel of the item formed from the first and second components. Inaddition, one or both of the molded components can be formed withvarious decorative features thereon that enable the components to morereadily form the desired appearance for the item.

Numerous other aspects, features, and advantages of the presentinvention will be made apparent from the following detailed descriptiontogether with the drawings figures.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings illustrate the best mode currently contemplated ofpracticing the present invention.

In the drawings:

FIG. 1 is an isometric view of a first embodiment of a tool handleconstructed according to the present invention;

FIG. 2 is an isometric view of the core used to form the handle of FIG.1;

FIG. 3 is isometric view of a first component molded over the core ofFIG. 2;

FIG. 4 is isometric view of a second molded component that is affixed tothe first component of FIG. 3;

FIG. 5 is an isometric view of a second embodiment of a tool handleconstructed according to the present invention;

FIG. 6 is an isometric view of the core used to form the handle of FIG.5;

FIG. 7 is isometric view of a first component molded over the core ofFIG. 6;

FIG. 8 is isometric view of a second molded component that is affixed tothe first component of FIG. 7.

DETAILED DESCRIPTION OF THE INVENTION

With reference now to the drawing figures in which like referencenumerals designate like parts throughout the disclosure, an itemconstructed according to the present invention is indicated generally at100 in FIGS. 1-4. The item 100 is formed as a handle 102 that is used tohouse a suitable mechanism for a tool, such as a ratcheting or torquelimiting mechanism, though other types of mechanisms or the omission ofany operating mechanism is also contemplated.

The handle 102 is formed with a core 104 that is formed from any desiredand preferably rigid material, such as a metal or hard plastic. The core104 has a shape corresponding to the desired usage of the item or handle102, and thus can have any desired shape, though ergonomic shapes foruse on tools utilized in the medical industry are especially preferred.This core 104 is initially positioned within a mold conforming to thedesired shape of a first component 106 to be formed around the core 104.

The first component 106 is formed on the exterior of the core 104 in anysuitable manner, such as in a conventional molding process, andpreferably by an injection molding process. The material used to formthe first component 106 can be selected based on the desired propertiesfor the first component 106, such as resiliency, rigidity, tackiness,texture and appearance among others. The material used for the firstcomponent 106 also is selected based on its suitability for use in theparticular molding process to be used Finally, depending upon thedesired aesthetic appearance for the handle 102, the material selectedfor use in forming the first component 106 is also selected or modifiedto have the desired color.

Thus, to satisfy the above requirements for the first component 106, thematerials that can be utilized for the first component 106, include, butare not limited to various types of thermoplastic and/or thermosetmaterials, such as silicone materials, and in particular silicone rubbermaterials.

After the formation of the first component 106 on the core 104, thehandle 102 including the core 104 and the first component 106 is removedfrom that initial mold so that a second component 108 can be formed onthe handle 102 that is at least partially complementary in shape withrespect to the first component 106.

The second component 108 is formed in a separate mold having aconfiguration corresponding to the shape desired for the secondcomponent 108, such as a conventional molding process, including, butnot limited to injection molding. Additionally, the material ormaterials utilized to form the second component 108 include the sametypes of materials that can be used in forming the first component 106.Also, the second component 108 is preferably formed of a material havinga color different than that used to form the first component 106 toenhance the aesthetic appearance of the handle 102. Further, dependingupon the location and other optional purposes of the second component108 the material or materials used to form the second component 108 canbe selected to have different and/or complementary properties to thematerials used to form the first component 106. For example, the firstcomponent 106 can be formed of a material or materials that are morerigid when formed in the particular molding process. In contrast, thematerial selected for use in forming the second component 108 can bemore flexible and/or tacky when formed in the particular moldingprocess, to provide a different tactile feel to the second component 108in comparison to the first component 106. This tactile distinction,which can also be enhanced through the use of differently coloredmaterials for the first component 106 an the second component 108, canprovide the handle 102 with a non-visual indication of the properlocation for the hand of an individual on the handle 102 when utilizinga tool or other item incorporating the handle 102. The differentmaterials selected for use in forming the first component 106 and thesecond component 108 can also be selected based on other differingcharacteristics for the materials that provide a desired distinction onthe resulting handle 102 or other item 100, such as different wearcharacteristics, among others.

In a first embodiment illustrated in FIGS. 1-4, the second component 108is formed separately from the handle 102 including the core 104 and thefirst component 106. The second component 108 is formed of the desiredmaterial to have a shape that is directly complementary to a portion ofthe first component 106. Preferably, the second component 108 is formedto be an insert positioned within a recess 110 formed in the exterior ofthe first component 106. The recess 110 can have any desired shapeand/or configuration, such as including a number of projections 112therein, and the second component 108 is formed to be directlycomplementary to that shape for the recess 110, such as by having anumber of apertures 114 formed therein through which the projections 112can extend.

In this embodiment, the second component 108 is affixed within therecess 110 of the first component 106 in any suitable manner, such as bymechanically fixing the second component 108 therein, such as byfrictional contact of abraded portions or engagable portions of thecomponents 106 and 108, or by using a fastener (not shown) connected toone or both of the first component 106 and the core 104, by adhering thesecond component 108 to the first component 106 utilizing a suitableadhesive, or by welding the second component 108 to the first component106, such as by thermal or sonic welding, among other suitable means forsecuring the second component 108 to the first component 106.

In this embodiment, there can also be more than one second component 108secured to the first component 106, with each of the second components108 having the same or a different configuration from one another. It isalso contemplated that each of the second components 108 can be formedfrom multiple sections or pieces, each of which is subsequently disposedan secured within the recess 110.

Referring now to FIGS. 5-8, in a second embodiment for the item 100, thefirst component 106, which is molded around the core 104 in a first mold(not shown) in the same conventional manner as described with regard tothe first embodiment illustrated in FIGS. 1-4, includes a projection 116extending outwardly from the first component 106. The projection 116includes a ridge 118 around its periphery that separates the innerportion 120 of the projection 116 from the outer portion 122.Preferably, the ridge 118 has a configuration that enables the ridge 118to separate the portions 120 and 122 from one another, as well as toprovide a tactile locating feature on the exterior of the handle 102.After the formation of the first component 106 on the core 104, the core104 and the first component 106 are placed in a second mold (not shown)for the forming of the second component 108 around the core 104 and thefirst component 106, also in any of the aforementioned conventionalmanners. When the second mold is closed, the ridge 118 on the projection116 is engaged by the second mold to effectively seal off the innerportion 120 of the projection 116 from the remainder of the interior ofthe second mold. Therefore, when the material used to form the secondcomponent 108 is introduced into the second mold, the material isprevented from flowing into the inner portion 120 of the projection 116in the first component 106 due to the engagement of the ridge 118 withthe second mold used to define and form the second component 108. Theridge 118 can any suitable cross-sectional shape to enable it toeffectively seal against the second mold, such as elliptical, oval,rectangular, square or triangular, but preferably, the ridge 118 issemicircular in cross-section, and has a radius of from 0-2 mm. with aradius of about 1 mm being especially preferred. Thus, as opposed tosecuring the second portion 108 to the first portion 106 as an insertwithin a correspondingly shaped recess 110, as in the first embodiment,in this construction and method of forming the item 100, the secondcomponent 108 is molded directly over the first component 106 while apart of the first component 106 is sealed off, such that part of thefirst component 106 remains visible through the second component 108.This greatly reduces the complexity of forming the first component 106,other than the projections 116, because any imperfections in theremainder of the first component 106 are effectively covered by thesecond component 108. Preferably, based on the requirement for thesealing capability of the ridge 118, the materials used to form thefirst component 106 are chosen from those able to withstand thetemperatures and pressures exerted during the molding process, and thatare capable of forming a solid bond with the material forming the secondcomponent 108. Particularly preferred materials are silicone rubber andsimilar materials.

In this second embodiment, the number of projections 116 formed on thefirst component 106 can be varied as necessary or desired, dependingupon the shape of the item 100 and the desired appearance for the item100.

Additionally, in each of the above embodiments, the exposed portions ofeach of the first component 106 and second component 108 can includeindicia 126 positioned thereon or therein. The indicia 126 can be formeddirectly into the respective first component 106 or the second component108 during the molding process for these components, or can be formed asa third component 127 that is inserted within a complementary recess 128disposed in the component 106 or 108.

In the configuration where the indicia 126 are formed directly withinthe component 106 and/or 108, preferably the indicia 126 are formed as araised or recessed section 130 of the component 106 and/or 108. Afterformation, the section 130 can be further treated, such as by paintingor placing another material within the section 130 to change theappearance of the section 130 from the surrounding material forming thefirst component 106 or the second component 108.

In the configuration where the section 130 is formed separately from theparticular component 106 and/or 108, the section 130 can be formed ofany desired material with any desired color. Once formed, the section130 can be inserted and secured within the recess 128 using any of thesuitable means described previously regarding the attachment of thesecond component 108 to the first component 106 in the first embodimentof the invention. Additionally, the section 130 can have any desiredshape, such as a fanciful design inserted into a complementary-shapedrecess 128, or a more conventional polygonal or circular shape that canincluding a particular design therein, such that a number of sections130 can be created with a number of different designs thereon, but eachsection 130 having the same exterior profile to enable the sections 130to be interchangeable. The sections 130 can be secured within the recess128 in any suitable manner depending upon the particular materialutilized to form the sections 130, such as frictionally securing,adhering, thermally or sonically welding or molding the section 130within the recess 128.

Alternatively, one or both of the components 106 and 108 can be formedwith apertures (not shown) that expose portions of the core 104, or thatenable projections (not shown) from the core 104 to extend outwardlythrough the various components 106 and 108 to function as furtherdecorative features for the handle 102, or as improved gripping or otherutilitarian features for the handle 102, or both.

Various other embodiments of the present invention are contemplated asbeing within the scope of the filed claims particularly pointing out anddistinctly claiming the subject matter regarded as the invention.

1. A method for forming a molded component for an item, the methodcomprising the steps of: a) providing a structural core for the item; b)molding a first component over the core in a first mold, the firstcomponent having at least one recess and a ridge separating the at leastone recess from a remainder of the first component; c) sealinglyengaging the only the ridge with an interior of a second mold to sealoff the at least one recess from the remainder of the first component;and d) molding a second component in the second mold, the secondcomponent directly engageable within the at least one first recess inthe first component.
 2. The method of claim 1 wherein the step ofmolding the second component comprises molding the second component inthe second mold within the at least one recess directly over the firstcomponent and the core.
 3. The method of claim 1 wherein the ridge issemicircular in cross-section.
 4. The method of claim 3 wherein theridge has a radius of between 0 mm to about 2 mm.
 5. The method of claim4 wherein the ridge has a radius of about 1 mm.
 6. The method of claim 1further comprising the step of securing the second component to thefirst component.
 7. The method of claim 1 further comprising the stepsof: a) molding an insert in a third mold; and b) securing the insertwithin at least one second recess formed in one of the first componentor the second component.
 8. The method of claim 7 further comprising thesteps of: a) molding a number of interchangeable inserts havingidentical exterior dimensions and differing interior design elements;and b) securing at least one of the number of inserts within the atleast one second recess.
 9. The method of claim 1 wherein a materialforming the first component and a material forming the second componenthave different characteristics.
 10. The method of claim 9 wherein thefirst component material and the second component material havedifferent tactile characteristics.
 11. The method of claim 9 wherein thefirst component material and the second component material havedifferent aesthetic characteristics.
 12. A handle formed using themethod of claim
 1. 13. A handle formed using the method of claim
 2. 14.A handle for a tool, the handle comprising: a) a core formed form arigid material; b) a first component engaged with the core and includinga projection extending outwardly from the first component that includesa ridge disposed around a periphery of the projection; and c) a secondcomponent engaged with the first component, the second componentdisposed around the projection.
 15. The method of claim 14 wherein theridge is semicircular in cross-section and has a radius of between 0 mmto about 2 mm.
 16. A method for forming a molded component for an item,the method comprising the steps of: a) providing a structural core forthe item; b) molding a first component over the core in a first mold,the first component having at least one first recess and a projectionextending outwardly from the first component that includes a ridgedisposed around the periphery of the projection; c) sealingly engagingthe ridge with an interior of the second mold to seal off the projectionprior to molding the second component; and d) molding a second componentin a second mold, the second component directly engageable with thefirst component around the projection